I think there may be a race condition caused by the groff pipeline. Just to be sure, please try
echo foo | troff >&- My earlier command was causing troff to dump core when its stdout was closed (by grops exiting) before it finished writing. —b9 On Mon, Sep 28, 2020 at 7:04 AM G. Branden Robinson < g.branden.robin...@gmail.com> wrote: > At 2020-09-28T03:44:41+1000, John Gardner wrote: > > The error I get with groff 1.22.4 is different: > > > > $ echo foo | groff -Pbar > > grops: can't open file 'bar' > > I can't reproduce this either, with groff 1.22.4 (Debian) or groff git > HEAD. > > Regards, > Branden >